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-rw-r--r--arch/nds32/cpu/n1213/ag101/timer.c205
1 files changed, 205 insertions, 0 deletions
diff --git a/arch/nds32/cpu/n1213/ag101/timer.c b/arch/nds32/cpu/n1213/ag101/timer.c
new file mode 100644
index 000000000..c099c33ac
--- /dev/null
+++ b/arch/nds32/cpu/n1213/ag101/timer.c
@@ -0,0 +1,205 @@
+/*
+ * (C) Copyright 2009 Faraday Technology
+ * Po-Yu Chuang <ratbert@faraday-tech.com>
+ *
+ * Copyright (C) 2011 Andes Technology Corporation
+ * Shawn Lin, Andes Technology Corporation <nobuhiro@andestech.com>
+ * Macpaul Lin, Andes Technology Corporation <macpaul@andestech.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <faraday/fttmr010.h>
+
+static ulong timestamp;
+static ulong lastdec;
+
+int timer_init(void)
+{
+ static struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE;
+ unsigned int cr;
+
+ debug("%s()\n", __func__);
+
+ /* disable timers */
+ writel(0, &tmr->cr);
+
+#ifdef CONFIG_FTTMR010_EXT_CLK
+ /* use 32768Hz oscillator for RTC, WDT, TIMER */
+ ftpmu010_32768osc_enable();
+#endif
+
+ /* setup timer */
+ writel(TIMER_LOAD_VAL, &tmr->timer3_load);
+ writel(TIMER_LOAD_VAL, &tmr->timer3_counter);
+ writel(0, &tmr->timer3_match1);
+ writel(0, &tmr->timer3_match2);
+
+ /* we don't want timer to issue interrupts */
+ writel(FTTMR010_TM3_MATCH1 |
+ FTTMR010_TM3_MATCH2 |
+ FTTMR010_TM3_OVERFLOW,
+ &tmr->interrupt_mask);
+
+ cr = readl(&tmr->cr);
+#ifdef CONFIG_FTTMR010_EXT_CLK
+ cr |= FTTMR010_TM3_CLOCK; /* use external clock */
+#endif
+ cr |= FTTMR010_TM3_ENABLE;
+ writel(cr, &tmr->cr);
+
+ /* init the timestamp and lastdec value */
+ reset_timer_masked();
+
+ return 0;
+}
+
+/*
+ * timer without interrupts
+ */
+
+/*
+ * reset time
+ */
+void reset_timer_masked(void)
+{
+ static struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE;
+
+ /* capure current decrementer value time */
+#ifdef CONFIG_FTTMR010_EXT_CLK
+ lastdec = readl(&tmr->timer3_counter) / (TIMER_CLOCK / CONFIG_SYS_HZ);
+#else
+ lastdec = readl(&tmr->timer3_counter) / (CONFIG_SYS_CLK_FREQ / 2);
+#endif
+ timestamp = 0; /* start "advancing" time stamp from 0 */
+
+ debug("%s(): lastdec = %lx\n", __func__, lastdec);
+}
+
+void reset_timer(void)
+{
+ debug("%s()\n", __func__);
+ reset_timer_masked();
+}
+
+/*
+ * return timer ticks
+ */
+ulong get_timer_masked(void)
+{
+ static struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE;
+
+ /* current tick value */
+#ifdef CONFIG_FTTMR010_EXT_CLK
+ ulong now = readl(&tmr->timer3_counter) / (TIMER_CLOCK / CONFIG_SYS_HZ);
+#else
+ ulong now = readl(&tmr->timer3_counter) / \
+ (CONFIG_SYS_CLK_FREQ / 2 / 1024);
+#endif
+
+ debug("%s(): now = %lx, lastdec = %lx\n", __func__, now, lastdec);
+
+ if (lastdec >= now) {
+ /*
+ * normal mode (non roll)
+ * move stamp fordward with absoulte diff ticks
+ */
+ timestamp += lastdec - now;
+ } else {
+ /*
+ * we have overflow of the count down timer
+ *
+ * nts = ts + ld + (TLV - now)
+ * ts=old stamp, ld=time that passed before passing through -1
+ * (TLV-now) amount of time after passing though -1
+ * nts = new "advancing time stamp"...it could also roll and
+ * cause problems.
+ */
+ timestamp += lastdec + TIMER_LOAD_VAL - now;
+ }
+
+ lastdec = now;
+
+ debug("%s() returns %lx\n", __func__, timestamp);
+
+ return timestamp;
+}
+
+/*
+ * return difference between timer ticks and base
+ */
+ulong get_timer(ulong base)
+{
+ debug("%s(%lx)\n", __func__, base);
+ return get_timer_masked() - base;
+}
+
+void set_timer(ulong t)
+{
+ debug("%s(%lx)\n", __func__, t);
+ timestamp = t;
+}
+
+/* delay x useconds AND preserve advance timestamp value */
+void __udelay(unsigned long usec)
+{
+ static struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE;
+
+#ifdef CONFIG_FTTMR010_EXT_CLK
+ long tmo = usec * (TIMER_CLOCK / 1000) / 1000;
+#else
+ long tmo = usec * ((CONFIG_SYS_CLK_FREQ / 2) / 1000) / 1000;
+#endif
+ unsigned long now, last = readl(&tmr->timer3_counter);
+
+ debug("%s(%lu)\n", __func__, usec);
+ while (tmo > 0) {
+ now = readl(&tmr->timer3_counter);
+ if (now > last) /* count down timer overflow */
+ tmo -= TIMER_LOAD_VAL + last - now;
+ else
+ tmo -= last - now;
+ last = now;
+ }
+}
+
+/*
+ * This function is derived from PowerPC code (read timebase as long long).
+ * On ARM it just returns the timer value.
+ */
+unsigned long long get_ticks(void)
+{
+ debug("%s()\n", __func__);
+ return get_timer(0);
+}
+
+/*
+ * This function is derived from PowerPC code (timebase clock frequency).
+ * On ARM it returns the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+ debug("%s()\n", __func__);
+#ifdef CONFIG_FTTMR010_EXT_CLK
+ return CONFIG_SYS_HZ;
+#else
+ return CONFIG_SYS_CLK_FREQ;
+#endif
+}